The art-world provocateur Maurizio Cattelan has a way of subverting expectations. When he found himself uninspired and empty-handed for his first solo show in 1989, he shut the gallery door and posted a sign: "Torno Subito," or Be Back Soon. Two decades later, he has approached his first retrospective by making light of his career—quite literally. With the help of a sturdy aluminum truss and a network of cables, 128 of his pieces now hang en masse from the Guggenheim's rotunda, to be viewed in the round from the spiraling aisles. As The New York Times reported, two owners declined to lend their art; one can understand why. The taxidermy works, from a shrouded elephant to a golden retriever, speak to mortality, echoed by Cattelan's newly announced retirement from art-making. His irreverent streak shines through with the waxworks—Pope John Paul II laid out by a meteorite in La Nona Ora (The Ninth Hour, 1999), and a wall-mounted bust of supermodel Stephanie Seymour. If you want a closer look at the artworks and commentary by curators, gallerists, and the artist himself, naturally, there's an app for that.